Electric motor



NA. C. GILBERT ELECTRIC MOTOR.

Filed Nov. 26 1917 5 Sheets-Sheet l llllAllllFlllllllllll Dec. 11,1923., 1,476,708

I A. C. GILBERT ELECTRIC MOTOR Filed Nov. 26. 191.7 3 Sheets-Sheet 2 hln-d Dec. 11 1923o A. C. GILBERT ELECTRIC MOTOR 4 Filed Nov. 26. 1917 3 Sheets-Sheet 5 v l MM2-W7 Patented Dec. 11, 1923.

UNITED STATES PATENT OFFICE.

ALFRED C. GILBERT, 0F NEW HAVEN, CONNECTICUT, ASSIGNOR TO THE C. GILBERT COMPANY., 0F NEW.. HAVEN, CONNECTICUT, A. CORPORATION OF CONNECTICUT.

ELECTRIC MOTOR.

' To all t may cof/wcm.'

4 Be it known that I, ALFRED C. GILBERT, a citizen of the United States, residlng 1n l New Haven, county of New Haven, State of Connecticut, have invented certain new and useful Improvements in Electric Motors, of

`which the following is a full, clear, and exact description.

This 'invention relates to electric motors, and more particularly to electric motors for frictionally driving sewing machines and the like. y

(lne of the primary objects of the invention is to provide a portable electric motor of improved and simplified type for driving the htand wheel of a sewing machine by friction. The motor usually rests freely on the table of the sewing machine at one side of the usual hand wheel. The motor has a pulley on the shaft thereof which Will frictionally en age the hand wheels of most sewing mac lines at the sides thereof, and it has a base which is so constructed and arranged that the pulley/ will maintain its engagement with the machine wheel and will not tend to walk away from said wheel when it engages the latter at the side, as stated, although the motor base engages the table of the sewing machine by gravity only and can be 'readily picked up and removed from the operative position. The improved motor can be very readily placed in the operative 'position as it is unnecessary to wedge or jam the pulley under the machine wheel, and, therefore the load imposed on the motor is reduced and undue wear of the motor shaft bearings is prevented.

Another object of the invention is to provide an electric motor of the type indicated, in which reversal of the direction of rotation to accord with the different directions of rotation of different sewing machine wheels is unnecessary, and, therefore, as the use of a reversing switch in connection with the motor is dispensed with, the cost of the apparatus is correspondingly reduced. lVith my improved motor, in changin over from a machine drive in one directlon to a drive in the opposite direction, it is merely necessary toturn the motor end for end, and to place the driving pulley on the opposite end of the motor'shaft. The motor proper is so mounted relatively to the base that the respective ends of the motor shaft, both of which project out beyond the motor casing,

have approximately symmetrical movements of adjustment relatively to the base, and, therefore, an adjustment which is used for driving a `machine wheel in one direction may be substantially duplicated in driving another wheel in the opposite direction from the opposite end of the motor shaft.

Another object of the invention is to provide a very simple but efficient form of ivotal connection between the motor and its ase.

c To these and other ends, the invention conslsts in the novel features and combinations of parts to be hereinafter described and claimed. v

In the accompanying drawings:

Fig. l is a sideelevation of an electric motor embodying my improvements, showlng the same in position on the table of a sewing machine for driving said machine. In this view, the head and wheel of the sewlng machine are shown in dotted lines.

Fig. 2 is an end view of the'mtor, looking from the right-hand side of Fig. 1, with the machine wheel in full lines;

Fig. 3 is an end elevation of the motor, showing it in another adjustment with respect to a sewing machine wheel for drivingvsaid wheel in the opposite direction.

1g. 3A is a fragmentary view of the pulley end ofthe motor when the same is adjusted to the position shown in Fig. 3;

Fig. 4 is an enlarged section on the line 4-4of Fig. 1; I

Fig. 5 is an enlarged section on line 5- lof Fig. 2;

Fig. 6 is a top plan View of the motor base; and

Figs. 7 and 8 are details of the lug on the motor by means of which it is pivoted t0 95 the base.

In the particular embodimentjshown, my improved electric motor comprises a motor properllO mounted on a base 11 to tilt in a vertical plane. The motor proper may be 100 set -or clamped in any of a number of angular adjustments in this plane. The plane in question passes through the motor shaft 12, and in one of these adjustments said motor shaft is horizontal, as shown in Fig. 1.

The device for clamping or fixing the m0- tor proper relatively to the base may include a clamping screw 13. In the particular form shown, the'base is formed of a.

spider-like casting having four radial legs eof vas

* axis.

i ample shown,

the lower ends et which are provided leg rubber feet l which rest. on the table held magnet and Winding Within the casing -4 and an armatnre ofthe usual type listed to il; ae.

he shaft-l2. ln the present inst-ance', the casing et the member l@ is split transtvvo parts along the line l0, the tvvo sections l0, l0 being interconnected by screws i6 or the like. lin the particular example illustrated, the brushes (not shown) are mounted Within and carried by the section l0". The motor shaft l2 extends coinletely through the casing Aand has bearings in the respective sections thereof., each extremity ot the shalt being extended to an ap reciable distance beyond the outer tace oi' the corresponding.; casing section, so that a pulley l? may be tired to the shalt at either end thereof.

llt may be assumed that in the case illustrated in Figs. l and 2, the motorl isl placed 'on the table et a sewing machine at a point behind the center of the machine wheel relaversely into tively to the front of4 the sewing machine wherethe operator sits. The base ll rests by gravity on the machine table. ln the exthe motor shalt is substantially horizontal and in parallelism with the axis et' the sewing machine wheel 18. 'lf he pulley il' engagesfthe side ot the machine wheel somewhat below the center thereof in this case, although in other instances the motor will drive the machine wheel when the pulley is in horizontal alignmentl with the center ol the latter or is located at the upper portion et the periphery of said wheel. As illustrated, however. the pulley engages the eriphery of the wheel at such a distance helow the center that a line passing through the centers ot the motor shattand wheel shaft is at an angle of approximately 45 to a vertical plane passing through the Wheel The pulley engages the machine wheelby friction only. lt is undesirable to wedge the pulley against the wheel, because this puts too much of a load on the motor and causes it to slow up, and may even burn it out if too much resistance is encountered. 'lhe pulley also engages the machine wheel by friction only because in this manner undue wear of the motor shaft bearings is prevented.

lt will be evident that the motor may be very readily placed in the operative posi tion with respect to the machine wheel. The member 10 carrying the motor shaft is iirst adjusted so that the motor shaft will be preferably horizontal and the motor is then moved into place beside the machine wheel, as shown. The tilting` mounting of the member l0 relatively to the base permits The interior con- 1 vl() in any suitable manner.

. marred by the end ot' anregen the motor shaft to belocated horizontally when the base has to be inclined *in one er the other direction, and it also permits the motor pulley to be tilted up or down to engage the machine wheel it the pulley does not properly engagesaid wheel when the shaft is horizontal.

ltet'errin'p; new to the detail construction ot' the pivotal connect-ion between the mot/or proper and base, it will be observed that the member l() has a de tits in a corresponding y shaped socket in 'lhe lug 19 may ln practice, it will lusually be a. separate part securedto the member l() by screws or the like, but as this particular feature is not material to the present invention ll shall not describe it here in further detail. 'ilhe motor proper and the base are entirely separate trom eachv other andthe motor proper, when litt/ed out et the socket in the base, can he used for a large variety of purposes other than the driving et sewing machines. 'lhe pivotal or swinging movement oi the motor proper relatively to the base is provided by torming the lower surface et' the 'luaq 19 as a para oi a cylinder whose axis is directed transversely to the motor shaft, and the socket 20 et the base has a, corresponding concave surface which tits'the the lug, is semi-cylindrical and the socket 20 is correspondingly shaped to provide tor a tilt-ing movement ot the motor member in a vertical plane which assesthrough the `motor shaft and is para lel to a ver-tical plane passing through the machine wheel axis. The shaping,l et the lug 19 in the form ott' a halt cylinder 'with plain faces perpendicular to theaxis et the cylinder, and the socket beingl shaped correspondingly, always maintains the motor member in the vertical lane in which it swings, while permitting 1t to move freely in this plane. The construction thus permits ot' motion similar to that which would be permitted by a horizontal pivotassing through the cylinder, but obviates t; e actual l use of such a separate pivot member. By swingingthe motor member inthe socket'ot' the hase, the pulley l? may lbe elevated o r depressed, as indicated by the dotted lines in Fig. l. The set. screw 13, previously mentioned, serves to. tix the lug 19 rigidly in the socket 2() when the desired adjustment. has been obtained. In the particular form shown, the set screw acts aga-inst one of the upright side ifa-ees of the lug'. the axis of said sere-w being substantially horizontal and the threaded shank thereof passing laterally throughl one ot the side walls ot' the socket 20. 1n order tol prevent the side face ot the. lug from being int/ermee a suitable clamping device be-v lug. i ln the torni showin.,J

the screw, l prefer to' ending'lug li) which the middle portion ot' the spider-like base.

be secured 'to the member tile lill) lio llt)

tween the vscrew head andthe lug, and, in the particular example illustrated, this clamping device consists ofa sheet metal plate or shim 21 which 'has a. slot 22 at one end, through which the Set screw passes, and a downwardly bent rtion 23 at the other end, which extends inte the socket in substantial contact with one of the upright side walls 24 thereof. As will be seen from 4, the motor can be securely clamped to the base in the desired adjustment -by tightening the set screw 13, lthe` head of which pushes the lug 19 laterally in the socket 20 and holds one of the upright side faces of the lu in snug frictional engagement with one o the upright side faces of the socket. When -it is desired -to change -the angle of the motor relatively yto the base, it is merely necessary to release the set screw 13, whereupon the motor can be readily tipped in its socket in one orthe other direction. When the desired adjustment is obtained, the set screw is again tightened to hold the parts rigidly together.

VIt will be obvious that when the set screw 4has been loosened, the motor member can be very readily effected, and when the motor has been lifted from the base, it can be used for various purposes where the base is not uired. p

he lug 19, in the example illustrated. is provided with an opening 25, through which the conducting wires for the motor ass, as shown in Fig. 5. The-top of the ase at oneend of thesocket 20 is rovided with av groove 26, which is adapte to register with'the opening 25 in the lug, and which providesl a clearance space for the conductor wires when the motor is tilted downwardly at that end of the base socket. At the opposite end of the socket a similar groove 26 is provided, which will act in the same manner when the motor is turned end lfor end in the base. served that the lug 19 and the base socket are so shaped that they will fit each other whether one end of the motor member is located at one side of the base or at the other side. Thus, two distinct angular adjustments of the motor member relatively to the base are permitted (in both of which, however, the motor shaft is transverse to the longitudinal axis of the lug and socket), and the facility of assembling the motor and base is correspondingly increased. In the present example, the base is square and the legs are symmetrically disposed. When the motor member is placed in the base socket, it may be freely turned in a. vertical plane passing through the motor -shaft, so

as to tilt the motor pulley up and down, and this is true whether the motor is set in the socket in the manner shown in Fig.

1 or is turned through 180 ina horizontal plane. In both cases, the lug fits the socket and the set screwclamps the'parts together.

The motor sha-ft 12, as previously stated, extends beyond .the respective end faces of the motor casing, and the pulley 17 can be applied to either end of said shaft. This is a feature yof advantage when the motor is 'used for various purposes, but particularly where the motor is used for driving a sewing machine. In different Imakes of sewing machines, the wheels are intended to rotate in different directions. Fi 2 shows the case `where the machine weel, looking from the left-hand end of the machine, rotates in a counter-clockwise direction. In such a casethe motor is used in substantially the position shown in Fig. 2; that is to say, at the rear of the machine wheel relatively to the operator of the machine. clock-wise as viewed in Fig. 2, and, the pulley 17 being located somewhat below.' the center of the machine wheel axis, the direction of rotation of the wheel is such as Inot to cause the motor to walk away from the wheel. The weight of the base is sufficient to .maintain the pulley-in the desired frictional contact with the wheel periphery. The direction of rotation of the machine wheel is such as not to cause the motor to be thrown outward from the wheel. This might takel place if the wheel rotated in the opposite dlrection. In order to apply my improved motor to a sewing machine wherein the hand wheel rotates in a direction opposite to that first described. the pulley is placed on the opposite end of the motor shaft, and the motor is arranged as shown in Figs. 3 and 3^. Fig. 3^ corresponds to Fig. 2, and shows the motor arranged at the front side of the Wheel with the pulley somewhat below the center of the wheel axis. In this case, 'the machine wheel rotates clockwise, as shown in Fig. 3^. and the pulley rotates counter-clockwise.

'Here also the side of the machine wheel nt' vclamping device 21`. 22 des not interfere with the reversalof the motor member in the base member so as to provide for turning the motor Ashaft laterally throu h 180- without turning the base, and t at the clamping device will clamp 'the parts together properly whether the motor mena-l The motor shaft rotates las' reveieeand the other part havinga projecting member providedwith a plane face entering and fitting said socket, and 'means engageable with said face of said last. named member, in abutting relation to the same, for clamping thearts together, said socket engaging -mem er being withdrawable from said socket when said clamping means is moved out of abutting relation to said socket enaging member, said clamping means being ocated wholly outside of said socket engaging member.

9. VIn-an electric motor, a base having a segmental socket with two opposite v'side walls, a motor member havingl a segmental lug engagin .said socket between said side walls, and c amping means carried wholly by the base and located outside of said lug, but in abutting relation therewith, for clam ing the motor member to the base by frictlonally engaging one side face .of the lu with the opposing side face of the soc et.

10. In an electric motor, av motor member, a base, one of said parts having a lug pro vided. with a. plane face and the other'part having a socket in which said lug engages, and clamping means, comprising a clampin screw,.in' abutting relation to said face o said 1u for clamping the parts together.

11. n an electrlcmotor, a motor member, a base, one of Said parts having a socket with a cylindricaly lower vsurface and substantially vertical side surfaces, the other part having a lug with a cylindrical lower part fitting the cylindrical lower surface, whereby the motor member is adapted to be tilted in a vertical plane,and means independent of said lug and associated with.| one of the side Walls of the socket for clamping the parts together.

12. In an electric motor, a motor member, a base, one of said parts having a Socket with a cylindrical lower frsurface and substantially vertical side surfaces, the other part having a lug with a cylindrical lower part engaglngthe cylindrical lower surface, whereby the motor member is adapted to be tilted in a vertical plane, and means independent of said lug and associated with ono of the side walls of the socket for clamping the parts together, said clam ing means located wholly outside of said ug in abutting relation to one of the side faces of the lug, and the lug being freely withdrawable from the socket when the clamping meansl is withdrawn slightly from the side face of the lu 13. n an electric motor, a motor member and a base, one of said parts having a lu and the other part having a correspon vingly shaped socket provided with plane walls between which said lug fits,- the con-v tacting surfaces of said lug and socket being so shaped as to provide for a tilting movement of the motor member in one tively to the base without die employment of `a separate pivot member.

I14.' 111 an electric motor, a motor member havingaprojecting lug, a spiderlike base having a socket open at the top of the base, said socket having plane side walls between which said lug its, the' bottom of the lug and the bot-tom of the socket being shaped to provide for a tilting movement of the motor member relatively tothe base in one plane only without the employment of a separate pivot member.

15. In an electric motor, a motor member having a projecting lug, va spiderlike basev having asocket open at the top ofI the in one plane only without the employment" lane only rela base, said socket having plane sidewalls of a separate pivot member, and means as` sociated with the base and located outside of said-lug in abutting relation tothe latte for clamping the parts together.

`16. ln an electrlcmotor, a base having a socket, and a motor member having a pros jecting lug -fitting said socket, vthe contactlng surfaces of the lug and Socket being shaped to provide for a tilting movement of the motor relatively to/the base in one plane only.

17. In an electric motor, a base having a socket with plaine side walls, and a motor member havln a projecting lug provided with a side ace .itting said socket, the l y contacting surfaces of the lug and socket being so shaped as to provide for a tilting movement of the motor relatively to the base, and a clamping member associated with the base arranged to clamp the parte together b engaging a. side face of the lug, whereby t e motor member can be withdrawn from the base as soon as said clamping member is vslightly retracted from the lug face.

18. In an electric motor, a base member,

a motor member, one of said members hav-4 ing a socket with a curved bottom anda straight side face, the other member having a lug with a curved bottom engaging the socket bottom andwith a side face adjacent' the side face of the socket vand clamping means acting laterally on the vlug to orce its side face into tight frictional engagement with that of the socket, said lug being rzo reversible end for end in said socket independently of said clamping means.

19. In an electric motor, a base member having a socket in the upper part thereof,

with a curved bottom and a substantially upright side face, a motor member having a depending Ilug freely set in said socket, said lughaving a curvedl lower face engagend a clamping. device passing through one side well of the socket and adapted to' force the side fece of said lugin'to tight frictionel engagement with that of the socket, seid 'n lug being reversible in seid socket.

` 20. An electric motor comprising e baise member, e motor member, one of seid memmrs having ve. segmental socket end the g other heving e correspondingly sheped lug merope@ entering seid socket, end e" clamping screw vcoopereting with seid lug but located outside the same for demping the motormem ber to .the base in any of e plurality of enguler ndgustments about e horizontal exis, said motor member being freely lifteble from yseid bese when seid clamping means is'iooseneld.

' lin witness whereof, have hereunto set n@ my bend on the 23d de of November, 191?.

ALLER C. (HUBERT. 

